POI-associated EIF4ENIF1 mutations exhibit impaired translation regulation abilities

Various genetic variants have been found to be associated with the clinical onset of premature ovarian insufficiency (POI). However, when measured in vitro, the functional influence of the variants can be difficult to determine. By whole-exome sequencing (WES) of 93 patients with sporadic POI, we found a missense variant c.623G > A;p.R208H in the EIF4ENIF1 gene. In silico prediction of the variant using different algorithms suggested it might be a damaging variant. We compared the property of EIF4ENIF1 R208H and Q842P, a POI-related mutant that we reported previously, with wildtype (WT) protein using 293FT cells in vitro. Surprisingly, a change in subcellular distribution and granule forming ability (Q842P) and nuclear import capacity (R208H) was not observed, despite domain prediction evidences. Since EIF4ENIF1 was reported to inhibit translation, we employed T&T-seq, a translation-transcription dual-omics sequencing method, to profile gene expression upon overexpression of EIF4ENIF1 WT and mutants. EIF4ENIF1 WT overexpression group exhibited significantly (P < 0.0001) lower translation efficiency (TE) than empty vector or GFP overexpression control group. Surprisingly, EIF4ENIF1 Q842P overexpression failed to repress global translation, showing an overall TE significantly higher than WT group. Overexpression R208H significantly (P < 0.0001) lowered the overall TE, whereas exhibiting a reduced translation inhibitory effect on high-TE genes (TE > 2 in GFP control group). Several fertility-associated genes, such as AMH in Q842P group and SERPINE1 and THBS1 in R208H group, was translationally up-regulated in mutant groups versus WT control, suggesting a potential mechanism of mutated EIF4ENIF1 causing POI via impaired translation repression. It is further proposed that T&T-seq can be a sensitive evaluation tool for the measurement of functional alteration by variants in many other translational regulator genes, not only EIF4ENIF1, helping to eliminate misinterpretation of clinical significance of genetic variants.

TP63 truncating mutation causes increased cell apoptosis and premature ovarian insufficiency by enhanced transcriptional activation of CLCA2

BACKGROUND

Premature ovarian insufficiency (POI) is a severe disorder leading to female infertility. Genetic mutations are important factors causing POI. TP63-truncating mutation has been reported to cause POI by increasing germ cell apoptosis, however what factors mediate this apoptosis remains unclear.

METHODS

Ninety-three patients with POI were recruited from Beijing Obstetrics and Gynecology Hospital, Capital Medical University. Whole-exome sequencing (WES) was performed for each patient. Sanger sequencing was used to confirm potential causative genetic variants. A minigene assay was performed to determine splicing effects of TP63 variants. A TP63-truncating plasmid was constructed. Real-time quantitative PCR, western blot analyses, dual luciferase reporter assays, immunofluorescence staining, and cell apoptosis assays were used to study the underlying mechanism of a TP63-truncating mutation causing POI.

RESULTS

By WES of 93 sporadic patients with POI, we found a 14-bp deletion covering the splice site in the TP63 gene. A minigene assay demonstrated that the 14-bp deletion variant led to exon 13 skipping during TP63 mRNA splicing, resulting in the generation of a truncated TP63 protein (TP63-mut). Overexpression of TP63-mut accelerated cell apoptosis. Mechanistically, the TP63-mut protein could bind to the promoter region of CLCA2 and activate the transcription of CLCA2 several times compared to that of the TP63 wild-type protein. Silencing CLCA2 using a specific small interfering RNA (siRNA) or inhibiting the Ataxia Telangiectasia Mutated (ATM) pathway using the KU55933 inhibitor attenuated cell apoptosis caused by TP63-mut protein expression.

CONCLUSION

Our findings revealed a crucial role for CLCA2 in mediating apoptosis in POI pathogenesis, and suggested that CLCA2 is a potential therapeutic target for POI.

Divergent Associations Between Serum Androgens and Ovarian Reserve Markers Revealed in Patients With Polycystic Ovary Syndrome

BACKGROUND

The role of excess androgen in ovarian reserve remains unclear in patients with polycystic ovary syndrome (PCOS). Our study highlights the associations of serum androgen levels and ovarian reserve markers in PCOS and non-PCOS women.

METHODS

Totally 584 menstrual abnormalities women of 20-45 years were retrospectively evaluated at the Beijing Obstetrics and Gynecology Hospital between January 2021 to October 2021. The enrolled patients were classified into two groups: the PCOS group (n=288) and the non-PCOS group (n=296) based on the Rotterdam consensus for PCOS diagnosis. The serum androgens, including testosterone (T), free testosterone (FT, calculated), bioavailable testosterone (Bio-T, calculated), androstenedione (A2), dihydrotestosterone (DHT), dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEAS) were assessed with an in-house developed liquid chromatography tandem mass spectrometry (LC-MS/MS) method. The associations between the serum androgens and the hormone markers commonly used for evaluating ovarian reserve function, such as anti-mullerian hormone (AMH) and the ratio of luteinizing hormone (LH)/follicle stimulating hormone (FSH) were explored.

RESULTS

The serum T, FT, Bio-T, A2, DHT, DHEA, DHEAS, AMH and LH/FSH of the PCOS group were 51.7 ± 23.2 ng/dL/mL, 8.5 ± 5.0 pg/mL, 210.1 ± 127.7 pg/mL, 1.9 ± 0.8 ng/mL, 0.2 ± 0.1 ng/mL, 6.4 ± 4.2 ng/mL, 2431.0 ± 1030.7 ng/mL, 6.7 ± 3.8 ng/mL, and 1.8 ± 1.4 respectively, which were significantly higher than those in the non-PCOS group (p<0.05). In the group of PCOS patients, T and A2 levels were positively associated with AMH in both multivariate linear regression analysis and Pearson's correlation analysis. Similar but weaker associations were observed in the non-PCOS patients. In the PCOS patients with hyperandrogenemia (HA), the AMH level was significantly higher in the subjects with T increased than in the subjects with non-T androgen(s) increased (A2, DHT, DHEA or DHEAS).

CONCLUSIONS

The serum androgen levels are positively associated with ovarian reserve markers in both of the PCOS and the non-PCOS patients in our study. In the PCOS group, the highest AMH level was observed in the subjects with the T elevation subgroup, suggesting that T is more closely related with the increase of AMH when compared with other androgens investigated.

Extensive serum biomarker analysis in the prethrombotic state of recurrent spontaneous abortion

The prethrombotic state (PTS) is a possible cause of recurrent spontaneous abortion (RSA). The aim of this study was to identify serum biomarkers for the detection of RSA with PTS (PSRSA). A Quantibody array 440 was used to screen novel serum‐based biomarkers for PSRSA/NRSA (RSA without PTS). Proteins differentially expressed in PSRSA were analysed using bioinformatics methods and subjected to a customized array and enzyme‐linked immunosorbent assay (ELISA) validation. We used receiver operating characteristic to calculate diagnostic accuracy, and machine learning methods to establish a biomarker model for evaluation of the identified targets. 20 targets were selected for validation using a customized array, and seven targets via ELISA. The decision tree model showed that IL‐24 was the first node and eotaxin‐3 was the second node distinguishing the PSRSA and NRSA groups (an accuracy rate of 100% and an AUC of 1). Epidermal growth factor (EGF) as the node distinguished the PSRSA and NC groups (an accuracy rate of 100% and an AUC of 1). EGF as the node distinguished the NRSA and NC groups (an accuracy rate of 96.5% and an AUC of 0.998). Serum DNAM‐1, BAFF, CNTF, LAG‐3, IL‐24, Eotaxin‐3 and EGF represent a panel of promising diagnostic biomarkers to detect the PSRSA.

[Application of pump-controlled retrograde trial off in weaning from veno-arterial extracorporeal membrane oxygenation in adult patients]

Objective: To Summarize the experience of pump-controlled retrograde trial off (PCRTO) in the process of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) withdrawal in adult patients. Methods: Adult patients who received ECMO assistance in Intensive Care Unit for Cardiac Surgery from March to July 2019 were collected. According to our strategies, PCRTO was used if the patients can wean from VA-ECMO and hemodynamic indexes were recorded during the process. The statistics data was collected, including the 48 hours survival rate, ECMO re-assistance rate, thrombus complications, Intensive Care Unit (ICU) stay time and hospital stay time after weaning from VA-ECMO. The patients who failed in the test were continued to be assisted by ECMO. Results: There were 46 patients assisted by VA-ECMO in our center. In total, 21 adults who met the offline test standard underwent 26 PCRTOs, including 10 male adults (47.6%), with an age of 65 (55, 68) years old. Eighteen adults passed the withdrawal test. No new thrombus was found in the arteriovenous ultrasound of the lower extremity after weaning from ECMO, and no pulmonary embolism was found in the chest X-ray. The success rate of weaning from ECMO was 69.23%(18/26). The D-dimer decreased [584(348,2 107)μg/L vs 1 440(631,2 916)μg/L, P=0.014] and the left ventricular ejection fraction (LVEF) increased (51.4%±8.5% vs 46.9%±10.6%, P=0.013) on the next day after weaning. There were significant differences in heart rate (HR), central venous pressure (CVP), oxygenation index and lactate (Lac) during the PCRTO in the group which involved the cases of the 8 failed experiments (all P<0.05). Compared with the failure group, there were significant differences in age, blood flow rate, CVP before the test, HR, pulse oxygen saturation(SpO(2)), CVP, Lac and oxygenation index after the test, and the variations of SpO(2), CVP and Lac. Conclusion: PCRTO is a simple, reversible, safe and effective weaning method. It can be used in the process of VA-ECMO withdrawal in adult patients.

Wenshen Yangxue decoction improves endometrial receptivity recovery and promotes endometrial angiogenesis in a rat model

CONTEXT

Wenshen Yangxue decoction (WSYXD) is a famous traditional Chinese medicine (TCM) formula and has been used in infertility treatment, but the exact mechanism is still unknown.

OBJECTIVES

To determine if WSYXD improves endometrial receptivity recovery and promotes endometrial angiogenesis in a rat model.

MATERIALS AND METHODS

A total of 100 proestrus female SPF Wistar rats were randomly assigned into five groups: control (saline), model (saline and hydroxyurea solution), high (5.2/100 g), middle (2.6/100 g) and low (1.3/100 g) WSYXD dose groups for 10 d. The microvessel densities, endometrial microstructure, as well as blastocysts number, were observed, followed by detection of angiogenesis-related gene/protein expression by immunohistochemistry, western blot and quantitative real-time polymerase chain reaction (RT-PCR), respectively.

RESULTS

Compared with the model group, the blastocyst number in WSYXD middle and high groups were significantly increased (4.50 ± 3.11 vs. 13.00 ± 2.12, 14.00 ± 1.83, p < 0.01). Lower MVD can be found in the model group (4.7) when compared with the normal control (13.7), middle (8.4) and high (9.7) dose groups. Additionally, significant differences were observed in VEGF, HIF-1α, p-AKT, p-PI3K, Ang1 and Ang2 (all p < 0.01) among different groups.

DISCUSSION AND CONCLUSIONS

In conclusion, WSYXD could help endometrial receptivity recovery and promote endometrial angiogenesis through PI3K, HIF-1α signalling and VEGF expression regulation. This study provides molecular evidence for application of WSYXD in the clinic and promotes new drug development from TCM.

Chinese herbal decoction of Wenshen Yangxue formula improved fertility and pregnancy rate in mice through PI3K/Akt signaling

OBJECTIVE

Traditional Chinese medicine (TCM) is an effective management to infertility. The association between TCM-mediated fertility and inhibition of phosphatidylinositol-3-kinase (PI3K) would be investigated.

METHODS

Institute of Cancer Research mice were treated with three herbal decoctions, named Wenshen Yangxue formula, Wenshen formula, and Yangxue formula, plus with human gonadotropins. PI3K inhibitor wortmannin was administrated to half of mice. Some index such as body weight, fertility ability would be investigated. The expression of P13K/Akt signaling was detected by using Western blot analysis.

RESULTS

No difference was observed in body weight among groups. Mice receiving the administration of human gonadotropins and herbal decoctions showed increased follicle numbers, percentage of fertilization, and promoted embryonic development. The treatment of Wenshen Yangxue formula decoction showed the highest efficiency, significant higher than Wenshen and Yangxue formulas. And increased the expression of p-PI3K and p-Akt proteins.

CONCLUSION

These results suggested the herbal decoctions promoted the fertilization of mice, which was related to the charge of PI3K/Akt activation.

Peacekeepers suffered combat-related injuries in Mali: a retrospective, descriptive study

PURPOSE

To describe the combat-related injuries cured by Chinese Level 2 medical treatment facility (CHN L2) in Mali from 1 March 2016 to 1 March 2018, including type of weapon, mortality, nature of injuries, degree and location of injuries and surgical procedures. METHODS : A retrospective, descriptive study of 176 injured cases that met the terrorist attacks was conducted. The medical data were collected by an electronic database system. All collected data were entered into an Excel spreadsheet for calculation.

RESULTS

We found that improvised explosive devices (114/176, 65%) were the most commonly used weapons of attack in Mali. 68.75% of the injuries (121/176) were classified as 'minor injuries according to Abbreviated Injury Scale score. As one patient may suffer multiple injuries, each location and nature of injuries was counted separately. Surface injuries were the top (116/197, 58.88%), followed by orthopaedic injuries (52/197, 26.39%) and internal injuries (29/197, 14.72%). The extremities were the most frequently injured body parts (144/197, 73.09%). We operated 175 surgeries to deal with the 176 combat-related injuries, which accounted for 40.05% of all 437 surgeries. The surgical debridement to remove fragments of explosive was the most frequently performed surgery. We also admitted 20 cases (18/176, 34%) into intensive care unit and transferred 40 cases to Level 3 medical facility. CONCLUSION : Peacekeepers taking protective measures for head and trunk frequently got surface injuries. And their unprotected extremities often got injured. The fragment removal was the top surgery and the damage control surgery was the highly technical nature surgery we performed. Chinese military should offer advanced surgical training course to military surgeons who carry out overseas operations.

Epstein-Barr virus infection and type I interferon signature in patients with systemic lupus erythematosus

Epstein-Barr (EB) virus infection has long been speculated to evoke systemic lupus erythematosus (SLE). Since a virus infection can induce interferon (IFN) system activation, we aimed to discover the relationship between the two in the progression of SLE in a Chinese inpatient cohort. Methods Peripheral blood mononuclear cells and sera were isolated from 116 SLE patients and 76 healthy controls. Antibodies against EBV-VCA (IgM and IgG) and EBNA (IgG) along with IFNα in patient sera were detected with enzyme-linked immunosorbent assays. The EB virus DNA load was detected by real-time quantitative polymerase chain reaction. Peripheral blood mononuclear cells both from patients and controls were isolated immediately. The mRNA from these samples was subjected to real-time PCR for the latent genes EBNA1, EBNA2 and LMP1 of EB virus, as well as four IFN-stimulated genes (ISGs) ( OASL, MX1, ISG15 and LY6E). The antibody results were used to determine the stage of EBV infection (lytic, latent, or previous). Results SLE patients had a higher rate of lytic infection defined as positive EBV-VCA IgM antibody (39.66% vs 10.53%, p = 0.027), but not the EB virus DNA load. Patients with lytic EB virus infection had higher SLEDAI scores than patients with non-lytic infection (15.24 ± 2.63 vs 13.79 ± 3.24, p = 0.012). LMP1 was the only EBV gene that had a higher expression level in SLE patients than in healthy controls (3.26 ± 2.95 vs 1.00 ± 2.89, p = 0.000). It was also positively correlated with SLEDAI scores ( r = 0.462, p = 0.000). Levels of IFNα and the four ISGs were all significantly higher in SLE patients than in healthy controls ( p < 0.05). LMP1 was positively correlated with the four ISGs ( r = 0.403 ∼ 0.494, p < 0.05) in SLE patients but not in healthy controls ( r = -0.153 ∼ 0.129, p > 0.05). Neither EBNA1 nor EBNA2 was correlated with the ISGs in SLE patients or in healthy controls. Conclusions The SLE patients had higher rates of lytic EB virus infection and higher latent gene LMP1 expression, which might be associated with the development and/or the progression of SLE via the type I IFN pathway. The underlying mechanism needs more study.

Serum biomarker analysis in patients with recurrent spontaneous abortion

Recurrent spontaneous abortion (RSA) occurs in 1–5% of parturients. The sustained therapy and research for RSA is expensive, which is a serious issue faced by both patients and doctors. The aim of the present study was to detect protein expression profiles in the serum of RSA patients and healthy controls, and to identify potential biomarkers for this disease. A 1,000-protein microarray consisting of a combination of Human L-507 and L-493 was used. The microarray data revealed that eight serum protein expression levels were significantly upregulated and 143 proteins were downregulated in RSA patients compared with the healthy controls. ELISA individually validated 5 of these 151 proteins in a larger cohort of patients and control samples, demonstrating a significant decrease in insulin-like growth factor-binding protein-related protein 1 (IFGBP-rp1)/IGFBP-7, Dickkopf-related protein 3 (Dkk3), receptor for advanced glycation end products (RAGE) and angiopoietin-2 levels in patients with RSA. Sensitivity and specificity analyses were calculated by a receiver operating characteristics curve, and were revealed to be 0.881, 0.823, 0.79 and 0.814, with diagnostic cut-off points of 95.44 ng/ml for IFGBP-rp1, 32.84 ng/ml for Dkk3, 147.27 ng/ml for RAGE and 441.40 ng/ml for angiopoietin-2. The present study indicated that these four proteins were downregulated in RSA samples and may be useful as biomarkers for the prediction and diagnosis of RSA. Subsequent studies in larger-scale cohorts are required to further validate the diagnostic value of these markers.

Genetic analysis of molecular markers for propamocarb residue in Cucumis sativus using quantitative trait locus mapping

The use of pesticides to protect plants against harmful organisms, such as pathogenic microorganisms, is one of the most effective ways to improve agricultural production. However, the continuous use of pesticides might present a risk to human health, animals, and the environment. In this study, two cucumber (Cucumis sativus) varieties containing different levels of pesticide residues, D9320 and D0351, were selected to establish an F₂ population. A genetic model and genetic linkage map were constructed. The results showed that the heredity of pesticide residues was dominated by an additive effect and was significantly influenced by non-additive factors in cucumber. QCp1 was detected as a quantitative trait locus (QTL) that might be involved in regulating the levels of pesticide residue in cucumber. Moreover, the cucumber genetic map was compared with the LG6 map, and the results indicated that this QTL was closely related to the level of pesticide residue in cucumber.

A food-grade fimbrial adhesin FaeG expression system inLactococcus lactisandLactobacillus casei

Enterotoxigenic Escherichia coli (ETEC) infection is the major cause of diarrhea in neonatal piglets. The fimbriae as colonizing factor in the pathogenesis of ETEC constitute a primary target for vaccination against ETEC. Lactic acid bacteria (LAB) are attractive tools to deliver antigens at the mucosal level. With the safety of genetically modified LAB in mind, a food-grade secretion vector (pALRc or pALRb) was constructed with DNA entirely from LAB, including the replicon, promoter, signal peptide, and selection marker alanine racemase gene (alr). To evaluate the feasibility of the system, the nuclease gene (nuc) from Staphylococcus aureus was used as a reporter to be expressed in both Lactococcus lactis and Lactobacillus casei. Subsequently, the extracellular secretion of the fimbrial adhesin FaeG of ETEC was confirmed by Western blot analysis. These results showed that this food-grade expression system has potential as the delivery vehicle for the safe use of genetically modified LAB for the development of vaccines against ETEC infection.

Attenuation of hind-limb suspension-induced bone loss by curcumin is associated with reduced oxidative stress and increased vitamin D receptor expression

Treatment with curcumin attenuated modeled microgravity-induced bone loss, possibly through abating oxidative stress and activating vitamin D receptor. Curcumin might be an effective countermeasure for microgravity-induced bone loss but remains to be tested in humans.

INTRODUCTION

Bone loss is one of the most important complications for human crewmembers who are exposed to long-term microgravity in space and also for bedridden people. The aim of the current study was to elucidate whether treatment with curcumin attenuated bone loss induced by microgravity.

METHODS

We used hind-limb suspension (HLS) and rotary wall vessel bioreactor (RWVB) to model microgravity in vivo and in vitro, respectively. We investigated the effects of curcumin consumption (40 mg kg(-1) body weight day(-1), via daily oral gavages) on Sprague-Dawley (SD) rats exposed to HLS for 6 weeks. Then, we investigated the effects of incubation with curcumin (4 μM) on MC3T3-E1 and RAW264.7 cells cultured in RWVB.

RESULTS

Curcumin alleviated HLS-induced reduction of bone mineral density in tibiae and preserved bone structure in tibiae and mechanical strength in femurs. Curcumin alleviated HLS-induced oxidative stress marked by reduced malondialdehyde content and increased total sulfhydryl content in femurs. In cultured MC3T3-E1 cells, curcumin inhibited modeled microgravity-induced reactive oxygen species (ROS) formation and enhanced osteoblastic differentiation. In cultured RAW264.7 cells, curcumin reduced modeled microgravity-induced ROS formation and attenuated osteoclastogenesis. In addition, curcumin upregulated vitamin D receptor (VDR) expression in femurs of rats exposed to HLS and MC3T3-E1 cells exposed to modeled microgravity.

CONCLUSION

Curcumin alleviated HLS-induced bone loss in rats, possibly via suppressing oxidative stress and upregulating VDR expression.

All fiber-coupled, long-term stable timing distribution for free-electron lasers with few-femtosecond jitter

We report recent progress made in a complete fiber-optic, high-precision, long-term stable timing distribution system for synchronization of next generation X-ray free-electron lasers. Timing jitter characterization of the master laser shows less than 170-as RMS integrated jitter for frequencies above 10 kHz, limited by the detection noise floor. Timing stabilization of a 3.5-km polarization-maintaining fiber link is successfully achieved with an RMS drift of 3.3 fs over 200 h of operation using all fiber-coupled elements. This all fiber-optic implementation will greatly reduce the complexity of optical alignment in timing distribution systems and improve the overall mechanical and timing stability of the system.

Sensitization of suberoylanilide hydroxamic acid (SAHA) on chemoradiation for human cervical cancer cells and its mechanism

PURPOSE

To explore the sensitization of suberoylanilide hydroxamic acid (SAHA) on chemoradiation for cervical cancer cells and its mechanism.

MATERIALS AND METHODS

After human cervical cancer SiHa cells were treated with SAHA and cisplatin (DDP) of different concentrations, inhibition and apoptosis rates, and cell cycle were detected. SiHa cells underwent radiation of various doses after treated with 20% IC50 of SAHA for 24 hours. The survival fraction of SiHa cells was calculated by colony-forming assay, and related parameters were calculated. mRNA and protein expressions of P21, Bax and Ku70 were detected.

RESULTS

The inhibition rate was higher in SD (SAHA combined with DDP) group than in D (DDP alone) group (p < 0.05). The number of cells in G0/G1 phase was higher, and the number of cells in G2/M+S phase and PI (proliferation index) were lower in S (SAHA), D, and SD groups than in control group, and in SD group than in S and D groups (p < 0.05). The apoptosis rate and the expressions of mRNA and protein of Bax and P21 were higher in SD group than in S or D group (p < 0.05). The cell survival fraction was lower in SAHA combined with radiotherapy group than in radiotherapy alone group (p < 0.05). Do, N, and Dq values were 2.329, 2.761, and 1.721, respectively, in radiotherapy alone group and 1.213, 4.770, and 0.823, respectively, in SAHA combined with radiotherapy group. SER was 1.92. Bax mRNA and protein expressions were higher but Ku70 mRNA and protein expressions were lower in SAHA combined with radiotherapy group than in radiotherapy alone group (p < 0.05).

CONCLUSION

SAHA promotes SiHa apoptosis in chemotherapy through up-regulation of mRNA and protein of p21 and Bax which leads to cell cycle arrest in G0/G1 phase. Low dose of SAHA promotes SiHa apoptosis and inhibits cell repair in radiotherapy through Bax up-regulation and Ku70 down-regulation.

Formononetin induces cell cycle arrest of human breast cancer cells via IGF1/PI3K/Akt pathways in vitro and in vivo

Formononetin is one of the main components of red clover plants, and is considered as a typical phytoestrogen. This study further investigated that formononetin inactivated IGF1/IGF1R-PI3K/Akt pathways and decreased cyclin D1 mRNA and protein expression in human breast cancer cells in vitro and in vivo. MCF-7 cells were treated with different concentrations of formononetin. The proliferation of the cells treated with formononetin was tested by MTT assay. The cell cycle in the treated cells was examined by flow cytometry. The levels of p-IGF-1 R, p-Akt, and cyclin D1 protein expression and cyclin D1 mRNA expression in the treated cells were determined by Western blot and RT-PCR, respectively. In addition, the antitumor activity of formononetin was evaluated in nude mice bearing orthotopic tumor implants. Compared with the control, formononetin inhibited the proliferation of MCF-7 cells and effectively induced cell cycle arrest. The levels of p-IGF-1 R, p-Akt, cyclin D1 protein expression, and cyclin D1 mRNA expression were also downregulated. On the other hand, formononetin also prevented the tumor growth of human breast cancer cells in nude mouse xenografts. These results show that formononetin causes cell cycle arrest at the G0/G1 phase by inactivating IGF1/IGF1R-PI3K/Akt pathways and decreasing cyclin D1 mRNA and protein expression, indicating the use of formononetin in the prevention of breast cancer carcinogenesis.

Structural differences between the Streptococcus agalactiae housekeeping and pilus-specific sortases: SrtA and SrtC1

The assembly of pili on the cell wall of Gram-positive bacteria requires transpeptidase enzymes called sortases. In Streptococcus agalactiae, the PI-1 pilus island of strain 2603V/R encodes two pilus-specific sortases (SrtC1 and SrtC2) and three pilins (GBS80, GBS52 and GBS104). Although either pilus-specific sortase is sufficient for the polymerization of the major pilin, GBS80, incorporation of the minor pilins GBS52 and GBS104 into the pilus structure requires SrtC1 and SrtC2, respectively. The S. agalactiae housekeeping sortase, SrtA, whose gene is present at a different location and does not catalyze pilus polymerization, was shown to be involved in cell wall anchoring of pilus polymers. To understand the structural basis of sortases involved in such diverse functions, we determined the crystal structures of S. agalactiae SrtC1 and SrtA. Both enzymes are made of an eight-stranded beta-barrel core with variations in their active site architecture. SrtA exhibits a catalytic triad arrangement similar to that in Streptococcus pyogenes SrtA but different from that in Staphylococcus aureus SrtA. In contrast, the SrtC1 enzyme contains an N-terminal helical domain and a ‘lid’ in its putative active site, which is similar to that seen in Streptococcus pneumoniae pilus-specific sortases, although with subtle differences in positioning and composition. To understand the effect of such differences on substrate recognition, we have also determined the crystal structure of a SrtC1 mutant, in which the conserved DP(W/F/Y) motif was replaced with the sorting signal motif of GBS80, IPNTG. By comparing the structures of WT wild type SrtA and SrtC1 and the ‘lid’ mutant of SrtC1, we propose that structural elements within the active site and the lid may be important for defining the role of specific sortase in pili biogenesis.

Air-soil exchange of mercury from background soils in the United States

The air-surface exchange of mercury (Hg) was measured, using a dynamic polycarbonate flux chamber, for soils with low or "background" Hg concentrations (<0.1 mg/kg) at eleven locations across the contiguous United States. Sampling locations included agricultural, desert, grassland, mixed and pine forest ecosystems (n=1326 soil flux measurements at 46 individual sites). An overall soil Hg flux of 0.9+/-0.2 ng/m2/h for these background soils was obtained by averaging the means for the different locations. Soil Hg fluxes were significantly lower in dark conditions than in the light for all but the grassland sites. Mean inlet air Hg concentrations were 1.0+/-0.1 ng/m3 in the dark and 1.3+/-0.2 ng/m3 in the light. Soil temperature inside and outside of the chamber, air temperature, relative humidity, and irradiance were measured concurrently with soil Hg flux. Soil-air Hg exchange was weakly predicted by environmental variables (R2 from 0.07 to 0.52). For a single location, flux was better correlated with soil moisture than other measured environmental parameters, suggesting that soil moisture might be an important driver for Hg emissions from background soils. In addition, based on data collected we suggest some quality control measures for use of Tekran 2537A analyzers when measuring low mercury fluxes. Using basic scaling procedures, we roughly estimate that natural emissions from soils in the contiguous U.S. release approximately 100 Mg/yr of Hg to the atmosphere.

[Kinetics of in vitro drug release from chitosan and N-alkyl chitosan membranes]

By using the so-called "lag-time" method, we studied the effect of membrane thickness(h), initial drug concentration(Co) and flow rate(V) on the difusion coefficient(D) of model drug in membranes. The experiment indicates that D increases as h and v increase; D Keeps constant when C0 changes; Under the same condition, the D value of N-alkyl chitosan membrane is bigger than that of pure chitosan membrane.

[Effect of temperature on the activity of some enzymes representative of EMP pathway and TCA cycle in psychrophilic yeast]

Some key enzymes of EMP pathway and TCA cycle in a psychrophilic yeast Y18 were studied in this paper compared with those of Saccharomyces cerevisiae. The results indicated that fructose, 1,6-bisphosphate aldolase, succinate dehydrogenase, and hexokinase in Y18 were very thermolabile and have high activity at low temperature. These enzymes belong to cold-active enzymes. Alpha-ketoglutarate dehydrogenase existed possibly in isoenzyme which had different temperature characteristics. Citrayl synthetase was very similar in temperature characteristics to that of mesophiles. The Km value of succinate dehydrogenase both from Y18 and S. cerevisiae were studied and Some features of enzyme in psychrophiles were also discussed in this paper.

[Clinical study on Shenqi Fuzheng injection combined with chemotherapy in treating malignant tumor of digestive tract]

OBJECTIVE

To assess the clinical effect and safety of Shenqi Fuzheng Injection (SQFZI) combined with chemotherapy in treating malignant tumor of digestive tract.

METHODS

One hundred and eighty-two patients were randomly divided into 3 groups, the combined therapy group (Group A), the SQFZI group (Group B) and the chemotherapy group (Group C). The remission and stabilization effect on cancer were observed.

RESULTS

The remission rate and stabilizing rate of Group A were 20.2% and 87.9%, and those of the Group C were 15.6% and 68.9%, the difference between the two groups was significant, P < 0.05. The symptom and living quality improving rate of Group A were 78.8% and 42.4% separately, those of the Group B were 73.7% and 68.4% and of the Group C 37.8% and 26.7% respectively, the inter-group differences were significant, P < 0.05. The weight gain rate and effective rate of Group A were 45.5% and 90.9%, of Group C were 13.3% and 40.0%, P < 0.05. SQFZI showed good protective effect on hematopoietic system, 7.7% patients in Group A with WBC count lower than 4 x 10(9)/L after treatment, while in Group C, the percentage reached 22.2%. Moreover, SQFZI could raise activity of NK cell, macrophage and T-lymphcyte subgroups, without any injury on heart, liver and kidney function or other adverse reaction.

CONCLUSION

SQFZI combined with chemotherapy has certain effect of remitting and stablizing on digestive tract tumor, the clinical effect is significant to patients with Qi-Deficiency, and is safe and reliable.

[Detection of chromosome aberrations in brain gliomas by primed in situ labelling]

To investigate the possibility of applying the primed in situ labelling (PRINS) method to detect chromosome aberrations in brain gliomas and eventually for pathological diagnosis, PRINS with chromosome 10 and 12 centromere specific primers as well as chromosome 1 telomere specific primer was carried out on tissues from 5 brain glioma cases, of which 4 cases were found to have monosomy 10 or loss of one copy of chromosome 10. The remaining case was found to have trisomy 12 and multi-copies of chromosome 1. It is suggested that PRINS is a new molecular cytological bio-technique which is faster, simpler and more efficient than conventional fluorescence in situ hybridization, and which may be clinically applied to detect chromosome aberrations in brain gliomas in the future.

NudF, a nuclear migration gene in Aspergillus nidulans, is similar to the human LIS-1 gene required for neuronal migration

During a study of the genetics of nuclear migration in the filamentous fungus Aspergillus nidulans, we cloned a gene, nudF, which is required for nuclear migration during vegetative growth as well as development. The NUDF protein level is controlled by another protein NUDC, and extra copies of the nudF gene can suppress the nudC3 mutation. nudF encodes a protein with 42% sequence identity to the human LIS-1 (Miller-Dieker lissencephaly-1) gene, which is required for proper neuronal migration during brain development. This strong similarity suggests that the LIS-1 gene product may have a function similar to that of NUDF and supports previous findings to suggest that nuclear migration may play a role in neuronal migration.

A new kind of fasciolicide: molecular and electronic structures of some o-hydroxybenzenesulfonanilides

The molecular and electronic structures of some fasciolicidal o-hydroxybenzenesulfonanilides (HBSA) have been studied using X-ray diffraction and semiempirical MO calculation. In these compounds, the phenolic hydroxyl forms a strong intramolecular hydrogen bond with an adjacent sulfonyl oxygen atom and the strength of the d-p dative S<--N bond, which may control the electron delocalization throughout the entire molecule, is affected by substituents on the phenyl rings on both sides. Owing to the poor delocalization, the contribution of the keto-form of the resonance structure is larger for some phenolate anions of HBSA in solution, and this may be a key factor determining the potency of fasciolicidal activity of HBSA.